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Omnipotence and the 'Delimiter of Possibilities' View

Aquinas notes that some analyses of omnipotence have a serious problem: they reduce the apparently substantive claim "God is omnipotent" to the trivial claim that God "can do all that He is able to do." Now, perhaps it is true that to be omnipotent is to be able to do everything God is able to do (or at least that omnipotence entails this), but this is hardly an illuminating analysis. In several places in his Anselmian Explorations, Thomas Morris defends the view that the Anselmian God is the 'delimiter of possibilities.' This view has been endorsed by other Anselmians, and...
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Divine Power, Alternate Possibilities, and Necessary Frankfurt Cases

Much of the difficulty in analyzing the notion of power comes from the various limitations of creaturely power: our powers come and go, and they are not infallible (sometimes we have the power or ability to do something, and nevertheless fail to do it when we try). These are the sorts of cases which derailed conditional analyses of power. However, an omnipotent being would have none of these limitations. In our paper, Alexander Pruss and I exploited this fact to develop an analysis of omnipotence, or unlimited power, without the need for a prior analysis of power. This approach has...
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The Value Component of Plantinga's Free Will Defense

A defense (in Plantinga's sense) against the logical problem of evil requires two components: a metaphysical component, which claims that a certain scenario is logically possible, and a value component, which claims that if the scenario in question were actual then it would be consistent with God's goodness to weakly actualize a world containing evil. In Plantinga's Free Will Defense (FWD), the scenario in question is one in which every creaturely essence suffers from transworld depravity (TWD). Now, in both The Nature of Necessity and God, Freedom, and Evil Plantinga's focus is squarely on the metaphysical component, defending the coherence...
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Counterpossible Reasoning in Philosophy of Religion (and Elsewhere)

The latest (July 2011) Faith and Philosophy contains an excellent article by Jeff Speaks on some difficulties related to establishing the consistency of certain claims (he uses as examples the existence of human freedom and the existence of evil) with the existence of an Anselmian God. The basic idea is this: since an Anselmian God is, by definition, a necessary being, establishing the possibility of an Anselmian God is tantamount to establishing the necessary, and therefore actual, existence of an Anselmian God. But these compatibility arguments typically, in one way or another, assume the possibility, and so the actuality, of...
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True and Immutable Natures in Descartes's Ontological Argument

In the Fifth Meditation, Descartes argues that "from the fact that I cannot think of God except as existing, it follows that existence is inseparable from God, and hence that he really exists" (CSM 2:46). Caterus famously replied with the 'existing lion' objection (parallel to Gaunilo's 'Lost Island'): we can't think of anything as an existing lion without thinking of it as existing, so the existing lion must exist (CSM 2:72). In fact, Caterus didn't need to add 'existing' at all: existence is a necessary condition for the exemplification of any property whatsoever. Nothing can be red, blue, five feet...
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A Leibnizian Cosmological Argument

Sobel's sixth chapter is devoted to, as he says, "proofs a contingentia mundi" (from the contingency of the world). The chief exponent here is Leibniz, though Sobel also considers Hume's Demea and his probable source, Samuel Clarke. Sobel argues that Leibniz's argument is valid ... by contradiction explosion. That is, he argues that Leibniz's premises are inconsistent. In this post, I show how to fix the argument using Leibnizian resources. In the next post, I will give another version of the argument which uses premises which I consider to be anti-Leibnizian, but which I think are more widely held than...
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Modal Collapse: Sobel's Objection to Gödel's Ontological Argument

The last ontological argument Sobel discusses is the Leibniz-inspired argument put forward by the famous logician Kurt Gödel. Gödel sets up a formal system in third-order quantified modal logic with equality and abstraction (!) and proves within that system the theorem: □∃xG(x) Where the predicate G is defined as follows: Gx ↔ ∀φ[P(φ) → φ(x)] Where P is primitive. (Sobel includes the complete source texts for Gödel's proof on pp. 144-146.) Now, unsurprisingly, given that the proof was originated by Gödel, everyone agrees that the proof is valid in the formal system. The question is whether there are any interpretations...
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Sobel's Argument Against Believing in the Possibility of a Perfect Being

My previous posts on Sobel's Logic and Theism, have been pretty favorable and made only minor criticisms or qualifications. In this post, my criticism will be much more strenuous for, in his criticism of modern modal ontological arguments, Sobel has made a serious error. Sobel wants to argue that there is no strong presumption in favor of the possibility of a perfect being, and that, because of contrary evidence (e.g. the problem of evil), if the ontological argument is to benefit the theist (by showing that, necessarily, there is a perfect being), rather than harm the theist (by showing that...
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Some Odd Brute Contingincies in Plantinga's Free Will Defense

Once upon a time, many philosophers believed that there was a logical problem of evil. That is, it was held that the (obviously true) proposition that there is some evil in the world logically entails that there is no God. (Where God is conceived as omnipotent and perfectly good.) I imagine that a lot of philosophers still believe this, but today few are arguing for it in print. Instead, atheist philosophers now typically put forth an evidentiary problem of evil. That is, they propound an argument something like this: The more evil there is, the less likely it is that...
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Quote of the Day: A Science Fiction Thought Experiment in Aristotle

Therefore, however many things appear to come about in different types of material, for instance, a circle in bronze and stone and wood, it seems clear that neither bronze nor stone is part of the substance of a circle, since they can be separated. But even for things that are not observed to be separated, there is no reason why the same results should not follow, just as even if all circles that were seen were bronze, nonetheless bronze would be no part of the form, but it would be difficult to separate them in thought. For instance, the form human is always observed in flesh and bones and these sorts of parts. Are these parts therefore part of the form and the definition [of human]? ...
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What Caused God?

In comments to my post on Dawkins and the Philosophers, atheist blogger Jonathan West has been pushing back against Michael Ruse's claim that Dawkins' prominent use of the "what caused God?" question is, as Jonathan puts it, 'fatuous.' Jonathan has also pushed this point in a recent blog post which considers this question in light of Swinburne's 'necessary being' arguments in The Existence of God. I will first make a few remarks about Swinburne's work in this area, and then proceed to show why the "what caused God?" question is indeed confused. To be fair, I admit...
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The Master Zombie Argument

Berkeley's so-called 'Master Argument' and Chalmers' 'Zombie Argument' are two famous arguments that turn on the relationship between conceivability and possibility. I have been thinking for some time about an amusing (and perhaps somewhat troubling) way of putting the two together. First, let me give simplified versions of the two arguments. The Master Argument (MA): (MA1) Whatever is conceived is conceived by some mind. (MA2) Whatever is conceived by a mind is in that mind. Therefore, (MA3) Nothing can be conceived that is not in a mind. (MA4) Whatever is inconceivable is impossible. Therefore, (MA5) It is impossible for anything...
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What Does Bayesian Epistemology Have To Do With Probabilities?

The answer to the question in the title of this post may seem obvious (after all, isn't Bayesianism all about probabilities?), but I think that the long discussion that followed Lauren's post on van Fraassen's objection to Bayesianism from quantum mechanics shows that it isn't clear at all - or at least, that it wasn't clear to either of us as we were discussing the issue. I think that I now understand why. In this post, I'm going to give three answers to this question, which I will call The Primitivist Account (P), The Kripkean Possible Worlds Account (KPW), and the Lewisian Possible Worlds Account (LPW). This post will discuss...
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Linguistic Ersatz Modal Realism and Types of Modality

David Lewis is best known for his modal realism, the view that all possible worlds exist in precisely the same sense that the actual world exists. He holds this view because he believes that it solves all sorts of philosophical problems related to modality, counterfactuals, properties, and so forth. However, there are a number of philosophers who think that the benefits of modal realism can be had without actually supposing that the possible world really exist. These philosophers Lewis calls ersatzers...
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